X0206 3 2021-07-19 0 0001380106 RAPID MICRO BIOSYSTEMS, INC. RPID 0001865779 Longitude Prime Partners, LLC 2740 SAND HILL ROAD, SECOND FLOOR MENLO PARK CA 94025 0 0 1 0 0001865844 Longitude Prime Fund, L.P. 2740 SAND HILL ROAD, SECOND FLOOR MENLO PARK CA 94025 0 0 1 0 Class A Common Stock 150000 I Held by Longitude Prime Fund, L.P. Represents shares purchased in the Issuer's initial public offering. Not included on this Form 3 are an additional 3,407,952 shares of Class A Common Stock and warrants to purchase an aggregate of 634,595 shares of Class A Common Stock held by Longitude Venture Partners II, L.P. ("LVP II"). LVP II, Longitude Capital Partners II, LLC, Patrick G. Enright and Juliet Tammenoms Bakker have separately filed a Form 4 in connection with the acquisition of the shares of Class A Common Stock described in this Form. The securities are held directly by Longitude Prime Fund, L.P. ("LPF"). Longitude Prime Partners, LLC ("LPP"), the general partner of LPF, may be deemed to have voting and investment power with respect to the shares held by LPF. Mr. Enright and Ms. Tammenoms Bakker are the managing members of LPP and may be deemed to have voting, investment and dispositive power over the shares held by LPF. LPP and each of Mr. Enright and Ms. Tammenoms Bakker disclaim beneficial ownership of such shares except to the extent of their respective pecuniary interests therein. Longitude Prime Partners, LLC, By: /s/ Patrick Enright, managing member 2021-07-20 Longitude Prime Fund, L.P., By: /s/ Patrick Enright, managing member of the general partner 2021-07-20